Artificial tooth



Dec. 22, 1942. R. E. OMORROW 23 I ARTIFICIAL TOOTH Filed June 5. 1940- INVENTPR Ross E. O Morrovv.

ATTORNEYS Patented Dec. 22, 1942 TENT OFFICE ARTIFICIAL TOOTH Ross E. OMorrow, The Columbus Columbus, Ohio, assignor to Dental Manufacturing Company, Columbus, Ohio} a corporation of Ohio Application June 5, 1940, Serial No. 338,964 2 Claims. (Cl. 32-8) My invention relates to artificial teeth. It has to do, more particularly, with replaceable porcelain artificial teeth suitable for use in either fixed or removable bridgework. My invention is applicable to interchangeable or replaceable facings, pontics, pin teeth, crown teeth, tube,

teeth and such other types as may be used in fixed or removable bridgework.

Natural teeth have been classified into three different forms in accordance with their general outline of crown, namely, tapering forms, and ovoid forms. Heretofore, only the square forms have been commonly used in bridgework and certain types of denture work. The tapering forms and ovoid forms cannot be used satisfactorily because of the large interdental spaces that exist inter-proximally between them and the adjacent tooth. Dentists desire to use artificial teeth having the ovoid and tapering forms whenever a patient presents such forms in his own natural teeth. However, because of the large inter-dental spaces referred to above, because of the darkened background of the oral cavity in daylight and particularly because of this darkened background under artificial light, these spaces appear most objectionable. Moreover, it has been impractical in these forms of artificial teeth to keep down the display of gold or vulcanite in the interdental spaces even where the technician makes an effort to construct a bridge or denture with a view of obscuring these other materials. It will be understood that these dark inter-dental spaces and the display of the other materials adds to the objectionable artificiality where tapering teeth and ovoid teeth are used. Because of these recited objections it has been common practice" for the dentist to select square forms of teeth more or less universally, and while such square forms tend to remove the above-mentioned objections, yet, a square form of artificial tooth supplied adjacent a natural tooth of the tapering or ovoid form has likewise been objectionable because it does not harmonize in appearance. These problems have commonly presented themselves in the anterior or frontal region of the mouth but to some extent have also appeared in the bicuspid region of the mouth.

It will be understood, by those skilled in the art, that in full denture construction the interdental space between theartificial teeth is filled in with the composition of the denture base material, such as vulcanite or condensite. It will also be understood that these denture base square forms,

what resembles the pink of the natural gum. Full denture restorations permit the use of all forms of artificial teeth which resemble the forms of natural teeth and the objectionable inter-dental spaces are properly filled in by the denture base material. Moreover, in full denture construction the natural gum of the patient is covered and shielded from view by the denture base material which, in the instance of upper dentures, extends far upwardly under the upper lip, whereas in bridgework construction and in most of the partial plate or removable denture construction, the artificial teeth are adapted to come into direct contact with the natural gum of the patient. This presents a difiicult problem when it is understood that the color of the natural gum changes in its degree of coloration or pinkness according to the general health of the patient. For example, under certain minor or major health disturbances the gum tissue may become more pale or pallid than normal, whereas, under certain other health disturbances the gum tissue may become more highly colored or flushed in relation to normal.

In an efiort to overcome the display of gold and other materials through the inter-dental spaces and'in an eifort to close up such interdental spaces, various expedients have been employed heretofore. Gne effort to overcome these objections has been to provide a special design of tooth which has inter-dental wings or flanges integrally formed on the tapering and ovoid forms. These wings or flanges: are made of the same white opaque tooth body as is used in the tooth portion proper. However, irrespective of the finesse of design, there appears too much white in the ensemble of the bridge or denture and the general outline of the tapering or ovoid tooth is adversely afiected and its detail of contour is lost. Other expedients have been used, such as, opaque porcelain carrying a certain concentration of pink pigment. The degree of coloration substantially equals a certain average value corresponding to the human gum coloration found in nature. Pink opaque porcelains of this nature are not unlike the pink used on gum'section teeth of the prior art. Moreover,

opaque pink porcelain has been supplied by various manufacturers in bulk powder form so that the dental ceramists can add pink opaque portions to the factory made tooth according to the materials contain a coloring pigment that some- 55 well known process and technique used by dentists and laboratory men. While efforts of this nature minimize the extensive display of the white porcelain, such pink additions have not restoration.

been found satisfactory. Where the manufacturers. supply the pink portion as an integral part of the tooth, the color value rarely matches the pink of the patients gum and where the technician attempts to match a patients gum in the dental ceramic technique, difiiculties are also encountered in obtaining the proper degree of pigmentation. Moreover, because of the opaque nature of these dental pink portions, they appear lifeless and artificial when placed in apposition with the natural gum. Furthermore, the dental ceramist finds other difficulties and objectionable features that appear from time to time as the patient wears such restorations. As recited above, thevarying health of the patient, with the accompanying color changes of the gum, such as,-paling and flushing of the tissue, cannot be compensated for in the opaque porcelain, with the result that the .pink restoration is seldom of the same pink value and seldom approaches pleasing color harmony with the natural gum tissue. Added to this problem is the problem of daylight illumination and artificial light illumination wherein there exists a marked difference, particularly in values associated with the red colors.

What has been said above in relation to the shortcomings of additions of opaque pink porcelain is more forcefully true where other materials such as pink vulcanite and pink con- 'densite are used for the same purposes.

In the prior art, pink stains have also been used around the collar area of artificial teeth for the purpose of subduing these inter-dental spaces and for the intention'of matching the gum tissue.

These efforts, like the other expedients mentioned above, have not been satisfactory for th various "reasons already given.

Aside from the objectionable appearance resulting from the large inter-dental spaces and the .showing of other materials through these spaces,

in association with taperingand ovoid forms of artificial teeth, there are certain functional disadvantages. Where these spaces exist, there is a tendency for. food particles to collect thereinand this detracts materially from the hygienic value of the restorative work. Such conditions makeit difficult to cleanse the restoration satisfactorily unless the patient has access to'a'toothbrush' and in some instances such toothbrush cle'ansingsca not be carried out to a satisfactory degree. In addition, these accumulated food particles have a tendency, through their fermentation and disintegration, to impair the healthy condition of the gum tissuewith the result that such dental restorations do not adequately meet the physiological requirements of'the dental art.

In the practice of dentistry, the practitioner is faced with another problem that is of particular importance in bridgework andv in partial denture work. It is a condition that frequently occurs during the extraction of a natural tooth, wherein due to certain conditions, such as extensive pathology, the labial portion or buccal portion of the bony 25 To overcome the with the natural teeth, but it is difficult to obtain this alignment and simultaneously extend the artificial tooth structure sufliciently gingival to make a satisfactory appearing and functioning restoration. When the artificial tooth is cut short at the gingival so that it is in alignment with the cervical line of the natural teeth, an unsatisfactory shelf or ledge will be present.- Where the artificial tooth is extended gingivally to fill in the depressed area it becomes most unsightly, in that it appears much longer than the crowns of the natural teeth. Efforts have been made to shape the gingival end of such tooth extensions so that they appear somewhat like the root of a tooth.

5 These latter efiorts have been unsatisfactory in that the patients mouth is unsightly and appears diseased. Other efforts have been made to correct this condition by shaping an artificial tooth structure that is intermediate between the above mentioned short restoration and long restoration.

Such efiortshave also been unsatisfactory inthat they present certain objections common to the objections raised in both the short and long restorations, recited above.

display of white porcelain, other materials, such as pink opaque porcelain and pink stains are used, but .they are objectionable for the same reasons that these materials are objectionable when used in inter-dental 3() spaces and in more localized areas near the gingival end of the tooth.

One of the objects of my invention is to provide artificial teeth for use in bridgework and in certain types of denture work having associated therewith integrally formed neck, collar, interdental or similar portions that will simulate the natural gum tissue of the oral cavityand will cover or shield from view the other materials of I which the bridge and denture are made, such as 4.0. goldor vulcanite.

Another object of my invention is to provide artificial teeth of such a nature that a variety of shapes of teeth may be successfully used in bridgework construction and in certain types of denture construction and which will closelyapproach naturalteeth in appearance.

' Another objectof my invention is to provide artificial teeth of the type indicated of such a nature that the transparent or'translucent portions thereof will change and compensate, in color intensity properties, for the changes occurring from day to day in the natural gum tissue and which will simulate the natural gum values, with equal facility, under either daylight or artificial light.

By the present invention I overcome all of the objectionable features of the prior'art. I produce an artificial tooth with an integrally formed neck, collar or inter-dental portion of highly translucent or even substantially transparent porcelain. These translucent or transparent porcelain areas are provided with a pigment or pigments of an intensity and value that will not materially opacify the transparent or translucent structure of the jaw breaks away and is removed body and that will be comparable to the paler with the natural root of the tooth. Where such bony plates are lost the healing of the tissues leaves a depression of minor or major extent depending upon the amount of bone structure that has been lost.

- common in the upper anterior region and in the bicuspid region. Those skilled in the art appreciate the difficulties in providing a satisfactory The artificial teeth: should be. in proper alignment, on the curvature of the arch,

,' natural gum hues found in the human mouth. The areas. adjacent the gum tissues will innerently and commonly be somewhat weaker in color value than the surrounding tissue but by virtue Depressions of this nature are of the color influence of the surrounding'tissue rounding and underlying natural tissue, in respect to the transparent or translucent pigmented body, will compensate for the day-to-day changes that occur in the natural tissue. Thereby, under varying conditions of health, the artificial struc ture will appear more pale or more flushed than normal according to the changes in the natural gum tissues. Moreover, with my artificial tooth structure the color value harmonies are maintained equally as well under conditions of daylight and artificial light.

Although I prefer that the artificial tooth structure be provided with the pigmented transparent or translucent areas, I also contemplate providing a porcelain powder for this same purpose, whereby the dental ceramic technician has available a means for forming additions of an extensive nature or of a peculiar shape, not commonly required in a manufactured tooth. The porcelain powder referred to may be of lower fusing properties but all shall remain substantially the same as the integral portions of the tooth discussed above.

The preferred embodiment of my invention is is illustrated in the accompanying drawing wherein similar characters of reference designate corresponding parts and wherein:

Figure 1 is a perspective View of a tooth or facing illustrating my invention.

Figure 2 is a side view of a pin facing having a transparent or translucent area according to my invention.

. Figure 3 is a vertical sectional view taken through the tooth shown in Figure 2.

Figure 4 is a vertical sectional view of an inerchangeable facing in which my invention has been embodied.

Figure 5 is a vertical sectional view of a pontic ooth in which my invention has been embodied.

Figure 6 is a vertical sectional view of a porcelain biting edge facing in which my invention has been incorporated.

Figure 7 illustrates the anterior teeth of a natural mouth with one tooth missing.

Figure 8 is a similar view illustrating how a tooth made according to my invention may be inserted in the opening caused by removal of the natural tooth.

Figure 9 is a similar view showing the artificial tooth in position.

Figure 10 is a vertical sectional view taken substantially along line Illof Figure 9 through the artificial tooth.

Figure 11 is a perspective view of an artificial tooth made according to my invention having a translucent portion of sufficient extent to fill in depressions caused by the loss of bone structure incident to extraction.

Figure 12 represents four upper incisor teeth made according to my invention.

According to my invention, I preferably mold a tooth so that that portion commonly known as the neck or collar will be made from a highly translucent, or as is better known today, of a transparent porcelain. The area that I propose to construct from this transparent or translucent porcelain may also be extended along such of the proximal areas in the gingival third of this tooth as will meet the requirements of good tooth form or anatomy. This transparent porcelain area is of a pink hue to, more Or less, simulate the color of the natural gum tissue in the mouth. However, it is preferably somewhat weaker in color value than the surrounding gum tissue so that it will transmit and reflect the normal other characteristics portion 2a 3 changes in color from underlying and surrounding gum tissue.

In Figure 1, I have illustrated a tooth or facing I in which my invention has been incorporated. This tooth I is provided with a collar or neck portion 2 which extends around the gingival end of the tooth and downwardly over the proximal sides thereof. This area 2 is made of translucent or transparent porcelain and is provided with a pink hue. In Figures 2 and 3 a pin facing is shown which is provided with the translucent similar to that shown in Figure 1. Figure 4 shows an interchangeable facing which is provided with a translucent portion 222 at the gingival end thereof according to my invention. Figure 5 represents a ponti'c tooth which is provided with a transparent portion 20 at the gingival end thereof according to my invention. Figure 6 illustrates a porcelain biting edge facing which is provided with a transparent porcelain portion 2d at the gingival end thereof.

In Figure 7, I illustrate the anterior teeth of a natural mouth having one tooth missing and which is adapted to be replaced with the artificial tooth I. In Figure 8, I illustrate how the tooth is positioned in relation to the ridge and Figure 9 illustrates the final position thereof. It will be noted from Figure 9 that the portion 2 will fill the interdental spaces between the artificial tooth I and the adjacent natural teeth. Itwill also fill the space left by the extraction of the natural tooth. This portion 2 will be of a pink hue and will simulate the natural gum. However, it will be of such a color value that it will transmit light rays'from the underlying gum tissue as indicated in Figure 10. It will also reflect light rays from the surrounding gum tissue.

In Figure 11, I illustrate a tooth or facing I a which is provided with an area 2c of translucent or transparent porcelain. This area 2e is of considerable extent so that it will fill in the depressions caused by the loss of bone structure incident to the extraction of a natural tooth which it is to replace. Where the loss of bone structure is exceptionally extensive, I preferably provide a porcelain powder having the translucent characteristics and properly pigmented for the dental ceramist to make such large additions as may be required.

In Figure 12, I have illustrated four upper incisor teeth as they would appear in a replacement bridge between abutments according to my invention. It will be noted from this figure that the interdental spaces have been filled and the labial portion of the natural gum is overlapped by the translucent portions of the artificial teeth made according to the teachings of this invention.

It will be apparent from the above description that I have provided an artificial tooth construction of such a nature that it will, for the first time, make it practical to use teeth of the same form, facial or crownal contour as nature has provided, irrespective of the size or shape required. Thus, a very natural appearance will be obtained. I have provided a means for eliminating the commonly objectionable interdental spaces and I have made it possible to construct bridges with interdental areas simulating those normally found in nature before extraction. The translucent or transparent portions of the artificial teeth which I have provided will cover or shield the gold, vulcanite or materials other than porcelain, and will hide them from view, thus minimizing the artificiality and providing a more 4 lifelike restoration; I also provide means for measurably filling in sunken areasoccurring' incident to the loss of the underlying bone structure whereby the artificial part is inconspicuous and whereby it harmonizes with the contour and color of the naturalgum tissue. The tooth structure which I have provided is such that the translucent or transparent portion which fills in the interdental spaces or other spaces will change and compensate in color intensity for the changes occurring in the natural gum tissue.

Various other advantages will be apparent from the preceding description, the drawing and the following claims.

In the following claims where I refer to translucent it is to be understood that I also intend to cover transparent.

Having thus described my invention, what I claim is: V

1. An artificial tooth of the type described comprising a substantially opaque body portion, a relatively transparent addendum on said body portion, said addendum extending across the gingival end of the body portion from the labial aspect to the lingual aspect and along the proximal sides of the body portion to an extent short of the incisal edge of said body portion.

24 An artificial tooth of the type described comprising a substantially opaque body portion, a relatively transparent addendum on said body portion, said addendum being disposed at the gingival end extending from the labial aspect to the lingual aspect and along the proximal side of the body portion to an extent short of the incisal edge of said body portion.

ROSS E. OMORROW. 

